In recent years, LTPS (Low Temperature Poly-silicon) technology has been developed continuously. As to a liquid crystal panel produced through the LTPS technology, an aperture ratio of the panel can be improved, brightness thereof can be improved, and power consumption thereof can be reduced. Therefore, the LTPS technology can be used for producing a product with a light weight, low power consumption and a high resolution. Since a carrier mobility ratio is improved, under an action of a strong electric field, carriers will drift and accelerate continuously along an electric field direction. The carriers can obtain a large kinetic energy to become hot carriers. The hot carriers can enter into a surrounding oxide layer directly or enter thereinto through a tunnel effect, and thus a property of a device will be affected, which is called as a hot carrier effect.
The hot carrier effect will severely influence an off-state current of a TFT (Thin Film Transistor) component. With respect to the TFT component, carrier in an N-type TFT is electron, and carrier in a P-type TFT is hole. A mobility ratio of electron is about 50 times that of hole, and thus the N-type TFT has a more obvious hot carrier effect. At present, a normal practice of controlling the hot carrier effect is to ignore the hot carrier effect in a PMOS (P-type Metal Oxide Semiconductor) transistor component and merely reduce the hot carrier effect in an NMOS (N-type Metal Oxide Semiconductor) transistor component. An ion implantation method is mostly used, i.e., a symmetrical LDD (lightly doped drain) structures are arranged between heavy doping source area and drain area on two sides of a gate and polysilicon. According to this method, only the hot carrier effect of the NMOS component can be alleviated, while the hot carrier effect of the PMOS component cannot be alleviated.